In almost all the cases, someone failed to first make an undercut when cutting a limb off, so they lost control of it and it landed tip first. Properly cutting a limb typically requires three cuts. The first two cuts are to remove the limb and are slightly out from the final cut. The removing cuts are an undercut, and then a top cut slightly out from the undercut. This should result in the limb breaking off cleanly and landing butt first (or nearly so). After the limb is removed, a final cut is made to remove the stub at the "branch bark collar".
This is also true when using a manual pole saw. Sometimes you have to adjust the blade (change the angle or flip it around) so you can make the undercut first.